Chan-Mo Yu

Highly regioselective palladium-mediated substitution of allylic and dienylic cyclic carbonates

Abstract Reaction of chiral allylic and dienylic cyclic carbonates with various nucleophiles in the presence of (PPh 3 ) 4 Pd as a catalyst afforded α-, γ-, or e-substituted products with high regio-, ( E )-stereo-, and diastereoselectivity depending on nucleophiles.

Catalytic allylic transfer reactions of functionalized aldehydes promoted by BINOL-Ti(IV) with synergistic reagent

Abstract Practical and efficient catalytic asymmetric allylic transfer reactions of tin reagents promoted by BINOL-Ti[OCH(CF 3 ) 2 ] 2 complex by the utilization of t -BuSBEt 2 are successful with a variety of functionalized aldehydes containing ketone, aldehyde, ester, amide, or carbamoyl functionality and affords products in high levels of enantioselectivity.

A novel allylic transfer reaction of chirally modified 2-borylbutadiene: synthesis of chiral homoallenyl alcohols

An enantioselective synthesis of the homoallenyl alcohols was achieved from the reaction of chiral 2-borylbutadiene with aldehydes through an allylic transfer reaction in good yields and enantioselectivities.

Highly diastereoselective Prins-type cyclisation of cyclopropylvinylic aldehydes mediated by TiCl4Electronic supplementary information (ESI) available: experimental details. See http://www.rsc.org/suppdata/cc/b4/b406362g/

A novel intramolecular Prins type cyclisation of cyclopropylvinylic aldehydes promoted by TiCl(4) under mild reaction conditions to form cis-cyclic products in high yields has been accomplished.

Pd(0)-Catalyzed Hydrogenolysis of Allylic and Dienylic Cyclic Carbonates: Synthesis of Optically Active Homoallylic Alcohols and Allylic Alcohols

Abstract Treatment of chiral allylic cyclic carbonates with ammonium formate in the presence of Pd(0) catalyst afforded optically active homoallylic alcohols with excellent regioselectivity. However, hydrogenolysis of dienylic cyclic carbonates in the presence of Pd(0) catalyst afforded conjugated or nonconjugated (E)-dienylic alcohols depending on Pd complexes used. Using homoallylic alcohol 3c as a chiral synthon, (R)-(+)-eldanolide, the sex pheromone of the African sugarcane stem borer, Eldana saccharina, was synthesized.

Regulation of equilibria in the catalytic asymmetric allylic transfer reaction: unusual 1,2-carbonyl addition of 3-trimethylsilyl-2-propenylstannaneElectronic supplementary information (ESI) available: experimental details. See http://www.rsc.org/suppdata/cc/b3/b304356h/

Catalytic enantioselective addition of 3-trimethylsilyl-2-propenylstannane to aldehydes promoted by BINOL–Ti(IV) catalyst along with synergistic reagent provides unusual 1,2-adducts with high levels of enantioselectivity.

Lewis acid-mediated cyclization of allenyl-aldehyde dimethyl acetals: synthesis of cis- and trans-2-haloalkenylcycloalkyl methyl ethers

Treatment of allenyl-aldehyde dimethyl acetals with iodotrimethylsilane, titanium tetrachloride, and indium trichloride afforded a mixture of separable cis- and trans-2-haloalkenyl substituted 2-haloalkenylcycloalkyl methyl ethers by intramolecular nucleophilic attack of allene moiety to the oxonium ion generated by the reaction of TMSI, TiCl4, or InCl3 to dimethyl acetal moiety.

Substituent influenced alkylation of 3-substituted 5-hydroxypyrazoles: Claisen rearrangement of 5-allyoxypyrazoles

Conspicuous substituent effects of 3-substituted 5-hydroxy-pyrazoles in the process of alkylation and subsequent [3,3]-sigmatropic rearrangement of the resulting alkylated products are described

Catalytic asymmetric dienylation of achiral aldehydes using buta-2,3-dienylstannane in the presence of chiral Lewis acid and synergetic reagent

Efficient catalytic asymmetric dienylation of achiral aldehydes with buta-2,3-dienyltributylstannane promoted by a BINOL-TiIV complex is achieved with high enantioselectivity by the utilization of Et2BSPri.

Catalytic asymmetric allylic transfer reaction: (4-trimethylsilylbut-2-ynyl)stannane as a new reagent leading to the enantioselective synthesis of dienyl alcohols

Catalytic enantioselective addition of (4-trimethylsilylbut-2-ynyl)tributylstannane to aldehydes provides trimethylsilylmethylallenyl alcohols in high enantioselectivity which can be converted with a second electrophile to the corresponding dienyl alcohols.